Percutaneously deliverable orthopedic joint device

ABSTRACT

A percutaneously implantable orthopedic device is a shape-changing joint prosthesis with a generally arcuate or generally rectilinear configuration which is delivered through a delivery device in a substantially straightened or slightly curved configuration into a joint in a patient. The generally arcuate configuration may include an open ring or spiral shape. The generally rectilinear configuration may include a polygon or zig-zag shape. The delivery and retrieval device can be a syringe, hypodermic needle or cannula. The orthopedic device is moveable into its generally arcuate or generally rectilinear configuration in the joint by manipulation or a shape memory set. The orthopedic device acts as a soft compliant bearing surface or cushion that minimizes the bone-on-bone wear from articulation and loading.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority from U.S. Provisional No. 60/911,056 filed Apr. 10, 2007, which is incorporated in its entirety by reference, herein.

BACKGROUND OF THE INVENTION

1. Field of Invention

Various embodiments of the present inventions relate to the treatment of osteoarthritis, rheumatoid arthritis, and any other joint degenerative process with a minimally invasive implantable device to reduce, amongst other things, bone-to-bone contact at a joint.

2. Related Art

Today there are an increasing number of patients with osteoarthritis, rheumatoid arthritis, and other joint degenerative processes. Osteoarthritis is by far the most common type of arthritis, and the percentage of people who have it grows higher with age. An estimated 12.1 percent of the U.S. population (nearly 21 million Americans) age 25 and older have osteoarthritis of one form or another. Although more common in older people it usually is the result of a joint injury, a joint malformation, or a genetic defect in joint cartilage. Its time of occurrence differs: osteoarthritis tends to start for men before the age of 45, and after the age of 45 it is more common in women. It is also more likely to occur in people who are obese or overweight and is related to those jobs that stress particular joints.

It affects the musculoskeletal system and specifically the joints—where two or more bones meet. It most often occurs in the hands (particularly at the ends of the fingers and thumbs), spine (particularly at the neck and lower back), knees, and hips. Joint problems can include; stiffness, inflammation and damage to joint cartilage (the tough, smooth tissue that covers the ends of the bones, enabling them to glide against one another) and surrounding structures. Such damage can lead to joint weakness, instability and visible deformities that, depending on the location of joint involvement, can interfere with the most basic daily tasks such as walking, climbing stairs, using a computer keyboard, cutting your food or brushing your teeth. This ultimately results in moderate to severe pain and joint deterioration. As this is a degenerative process of the joint it can ultimately end in total joint replacement. Drug regimes can provide temporary relief from the pain but do not slow down the crippling affects. The extreme result or end point in traditional treatments is an open surgery procedure for placing a spacer or total joint replacement with a prosthetic device. It would be desirable as well as beneficial if there were an intermediary step or alternative treatment before this extreme.

Current joint replacement therapies (spacers or a total prosthesis) require the joint capsule to be surgically opened and the bone surfaces to be partially or totally removed. Various spacers and or prosthetic devices can be made from a number of biocompatible polymers such as silicone, polyurethane, Teflon etc. Both modalities present drawbacks. For example, U.S. Pat. No. 6,007,580 to Matti Lehto et al. describes an implantable spacer that must be fixed at one or both ends to the bone of either end of the knuckle. It is not provided in a shape memory configuration and must be implanted by opening of the knuckle capsule. It further must be affixed at one or both ends to the corresponding bone faces.

Various spacers in the art can cause inflammation and the total joint replacement can limit the range of motion, compromise the strength and ultimately the stability of the joint. These surgeries are invasive and require the joint capsule to be surgically opened. The incision itself can result in inflammation and infection. Due to the invasiveness of the procedure and the delicate nature of the joint it can result in joint instability prolonged healing times.

SUMMARY OF THE INVENTION

It would be desirable to provide intermediary treatment before deciding whether to undergo total joint replacement. Such intermediary treatment preferably comprises providing a cushion or improved spacer made of shape-changing, shape-memory or shape-recovering material placed into the joint to minimize pain and slow the deterioration process. It would further be desirable to provide this cushion or improved articulation device in a minimally-invasive procedure; e.g., through a hypodermic needle, cannula or catheter that can be inserted directly into the joint without the necessity of a surgical cut-down procedure and its associated risks. There would be a distinct benefit to the patient in that there would be a reduction in pain, time, and complexity in conducting the procedure as well as decreasing healing time, reducing post-operative pain, and slowing of deterioration in a joint without the necessity of surgically opening the joint.

In various embodiments the orthopedic device is an implantable prosthetic that has a substantially non-linear preformed configuration (e.g. a shape that is not a substantially straight line, such as a generally arcuate shape or a generally rectilinear shape composed of more than a single line) which is delivered through a hypodermic needle in a straightened configuration and into the joint. In one embodiment the orthopedic device is an implantable prosthetic generally arcuate open ring or spiral which is delivered through a hypodermic needle in a straightened configuration and into the joint. Then due to its shape memory set, it then assumes an open ring. This ring acts as a compliant bearing surface which minimizes the bone on bone wear from articulation and loading. In another embodiment the orthopedic device is an implantable prosthetic generally rectilinear polygon or series of linear segment shape which is delivered through a hypodermic needle in a straightened configuration and into the joint.

In one embodiment the orthopedic device is an implantable prosthetic with a series of discrete articulatable elements. The elements, or segments, can be connected by one or more connectors. In one embodiment the orthopedic device is a ratcheted linkage. In another embodiment the orthopedic device is a series of articular layers on a bendable elongate core. In one embodiment the orthopedic device discrete articulatable elements can form a generally arcuate open ring or spiral. In various embodiments the orthopedic device may be delivered through a hypodermic needle in a straightened configuration and into the joint. After delivery, various embodiments of the orthopedic device can resume it generally rectilinear or generally arcuate configuration by being manipulated into that shape or due to a shape memory set. The orthopedic device can act as a compliant bearing surface which minimizes the bone on bone wear from articulation and loading.

In various embodiments, delivery or retrieval systems include a straight or curved hypodermic needle, syringe, cannula or catheter specially configured to implant or retrieve an orthopedic device with a specific orientation. Certain systems can include specially shaped plungers, needles, interlocks, removable attachments, pinchers, lassos, tethers, hooks, threaded interfaces, reservoirs, or cassette loading systems for interacting with or positioning the orthopedic device. In one embodiment the orthopedic device is an implantable prosthetic generally arcuate open ring or spiral which is delivered through a hypodermic needle in a straightened configuration and into the joint. Then due to its shape memory set, it then assumes an open ring. This ring acts as a compliant bearing surface which minimizes the bone on bone wear from articulation and loading. In another embodiment the orthopedic device is an implantable prosthetic generally rectilinear polygon or series of linear segment shape which is delivered through a hypodermic needle in a straightened configuration and into the joint.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, embodiments, and advantages of the present invention will now be described in connection with preferred embodiments of the invention, in reference to the accompanying drawings. The illustrated embodiments, however, are merely examples and are not intended to limit the invention.

FIG. 1A is a schematic top view of an orthopedic device according to one embodiment of the present invention comprising a substantially straight configuration.

FIG. 1B is a schematic top view of an orthopedic device according to one embodiment of the present invention comprising an open hoop arcuate configuration.

FIG. 1C is a schematic top view of an orthopedic device according to one embodiment of the present invention comprising a nautilus-style spiral arcuate configuration.

FIG. 2 is a schematic cross-section view perpendicular to a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising an elongate core and an articular layer surrounding at least a portion of the core.

FIG. 3A is a schematic cross-section view along a plane substantially parallel to and passing through a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising a substantially straight configuration, the device comprising an elongate core and an articular layer surrounding at least a portion of the core.

FIG. 3B is a schematic cross-section view along a plane substantially parallel to and passing through a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising an open hoop arcuate configuration, the device comprising an elongate core and an articular layer surrounding at least a portion of the core.

FIG. 3C is a schematic cross-section view along a plane substantially parallel to and passing through a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising a nautilus-style spiral arcuate configuration, the device comprising an elongate core and an articular layer surrounding at least a portion of the core.

FIG. 3D is a schematic cross-section view along a plane substantially parallel to and passing through a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising an open hoop arcuate configuration, the device comprising one or more elongate cores wrapped, braided or folded along a length of the device and an articular layer surrounding at least a portion of the core.

FIG. 3E is a schematic cross-section view along a plane substantially parallel to and passing through a longitudinal axis of an orthopedic device according to one embodiment of the present invention comprising a nautilus-style spiral arcuate configuration, the device comprising one or more elongate cores wrapped, braided or folded along a length of the device and an articular layer surrounding at least a portion of the core.

FIG. 4A is a schematic side view of an elongate core according to one embodiment of the present invention comprising one or more substantially linear or straight members.

FIG. 4B is a schematic side view of an elongate core according to one embodiment of the present invention comprising one or more wave, curve or zig-zag members disposed in one or more planes.

FIG. 4C is a schematic side view of an elongate core according to one embodiment of the present invention comprising one or more members in a braided or weave configuration.

FIG. 5A is a schematic top view of an elongate core according to one embodiment of the present invention comprising an open hoop arcuate configuration and one or more end pieces.

FIG. 5B is a schematic top view of an elongate core according to one embodiment of the present invention comprising an open hoop arcuate configuration and one or more bends or hooks.

FIG. 5C is a schematic top view of an elongate core according to one embodiment of the present invention comprising an open hoop arcuate configuration and one or more features bent in or out of the primary plane of the device.

FIGS. 6A-6K are schematic cross-section views of elongate cores according to various embodiments of the present invention.

FIG. 7A is a schematic perspective view of an orthopedic device according to one embodiment of the present invention comprising a plurality of independent or interconnectable discrete elongate members.

FIG. 7B is a schematic perspective view of an orthopedic device according to one embodiment of the present invention comprising a plurality of independent or interconnectable discrete elongate members in a “W” configuration.

FIG. 8 is a schematic perspective view of an orthopedic device according to one embodiment of the present invention comprising a plurality of independent or interconnectable discrete members.

FIG. 9A is a schematic side view of an elongate core according to one embodiment of the present invention comprising a plurality of interconnectable discrete members in a substantially straight configuration.

FIG. 9B is a schematic side view of one interconnectable discrete member of FIG. 9A.

FIG. 9C is a schematic side view of an elongate core comprising a plurality of interconnectable discrete members according to FIG. 9A in an arcuate open loop configuration.

FIG. 10A is a schematic side view of an orthopedic device delivery system according to one embodiment of the present invention comprising a handle and a plunger.

FIG. 10B is a schematic side view of an orthopedic device delivery system according to one embodiment of the present invention comprising a substantially straight cannula or needle with a lumen.

FIG. 10C is a schematic side view of an orthopedic device delivery system according to one embodiment of the present invention comprising an arcuate cannula or needle with a lumen.

FIG. 10D is a schematic side view close up of a distal end of an orthopedic device delivery system according to one embodiment of the present invention comprising a blunted delivery cannula.

FIG. 10E is a schematic side view of an orthopedic device delivery system according to one embodiment of the present invention comprising an angular tip.

FIG. 11 is a schematic side view of an orthopedic device delivery system according to one embodiment of the present invention comprising an implantable orthopedic device, a cannula, and a plunger.

FIG. 12A is a schematic side cross-sectional view of an orthopedic device delivery system according to one embodiment of the present invention prior to implantation in a joint.

FIG. 12B is a schematic top cross-sectional view orthogonal to FIG. 12A of two embodiments of orthopedic device delivery systems similar to the system of FIG. 12A prior to implantation in a joint, wherein on embodiment comprises a substantially straight cannula and the other embodiment comprises an arcuate cannula.

FIG. 13A is a schematic side cross-sectional view of an orthopedic device delivery system according to the embodiment of the present invention shown in FIG. 12A upon partial insertion of the orthopedic device into the joint.

FIG. 13B is a schematic top cross-sectional view orthogonal to FIG. 13A of two embodiments of orthopedic device delivery systems according to FIG. 12B upon partial insertion of the orthopedic device into the joint.

FIG. 14A is a schematic side cross-sectional view of an orthopedic device delivery system according to the embodiment of the present invention shown in FIG. 12A upon deployment of the orthopedic device into the joint.

FIG. 14B is a schematic top cross-sectional view orthogonal to FIG. 14A of two embodiments of orthopedic device delivery systems according to FIG. 12B upon deployment of the orthopedic device into the joint.

FIG. 15A is a schematic side cross-sectional view of an orthopedic device delivery system according to the embodiment of the present invention shown in FIG. 12A upon deployment of the orthopedic device into the joint and removal of the delivery cannula.

FIG. 15B is a schematic top cross-sectional view orthogonal to FIG. 15A of two embodiments of orthopedic device delivery systems according to FIG. 12B upon deployment of the orthopedic device into the joint and removal of the delivery cannula(e).

FIG. 16A is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising a tether and a loop structure in a substantially straight configuration.

FIG. 16B is a schematic side view of the orthopedic device of FIG. 16A in an arcuate configuration.

FIG. 16C is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising one or more tethers in an arcuate configuration.

FIG. 17 is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising a looped arcuate configuration and at least one anchor.

FIG. 18 is a schematic side view of an orthopedic device removal system according to one embodiment of the present invention comprising an implantable orthopedic device, a cannula, and a snare.

FIGS. 19A and 19B are schematic perspective and side views of a portion of an interface in an orthopedic device delivery and removal system according to one embodiment of the present invention comprising an implantable orthopedic device and a plunger connectable with a device interface.

FIGS. 20A-20C are schematic side views of a portion of an interface in an orthopedic device delivery and removal system according to another embodiment of the present invention comprising an implantable orthopedic device and a plunger connectable with a device interface.

FIG. 21A is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising a multiplanar spiral configuration.

FIG. 21B is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising a multiplanar arcuate configuration.

FIG. 21C is a schematic side view of an orthopedic device according to one embodiment of the present invention comprising a “W”-shaped configuration.

Throughout the figures, the same reference numerals and characters, unless otherwise stated, are used to denote like features, elements, components or portions of the illustrated embodiments. In certain instances, similar names may be used to describe similar components with different reference numerals which have certain common or similar features. Moreover, while the subject invention will now be described in detail with reference to the figures, it is done so in connection with the illustrative embodiments. It is intended that changes and modifications can be made to the described embodiments without departing from the true scope and spirit of the subject invention as defined by the appended claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As should be understood in view of the following detailed description, this application is primarily directed to apparatuses, systems and methods for minimally-invasive treatment of bone joints. In various embodiments, an orthopedic device suitable for minimally invasive deployment using a tubular delivery apparatus with a lumen or channel, such as a cannula, hypodermic needle, catheter, or another similar apparatus. In various embodiments the orthopedic device is an implantable prosthetic that has a substantially non-linear pre-formed configuration (e.g. a shape that is not a substantially straight line, such as a generally arcuate shape or a generally rectilinear shape composed of more than a single line) which is delivered through a hypodermic needle in a straightened configuration and into the joint. In one preferred embodiment of the invention, an orthopedic device comprises an elongate shape memory body that has a generally arcuate configuration to enhance self-centering positioning of the orthopedic device when deployed. In another embodiment an orthopedic device comprises an elongate shape memory body that has a generally rectilinear configuration to enhance self-centering positioning of the orthopedic device when deployed. In one embodiment an orthopedic device comprises a plurality of elongate shape memory bodies that can be moved into a configuration to enhance self-centering positioning of the orthopedic device when deployed. The body can be manipulated into a substantially straight configuration to permit delivery. In various embodiments, the orthopedic device can be for single or multiple uses, and may be removed from the joint.

1. Implantable Orthopedic Devices

In various embodiments the orthopedic device can have an arcuate configuration once it is implanted in a joint. As used herein, “arcuate” may refer to curved or rounded configurations or shapes, but can also include generally arcuate configurations and shapes that have some straight aspect or element with curved or rounded configurations or shapes. As used herein, arcuate and generally arcuate shapes can include “C”, “O”, “S”, spiral, nautilus, “Q” and other generally arcuate shapes. Similarly, certain embodiments of the orthopedic device may include rectilinear configurations, which can include polygons such as triangles, squares, rectangles, diamonds, rhombuses, pentagons, hexagons, octagons and other shapes with generally straight edges, and further including shapes and configurations that are generally rectilinear having some curved edge or comers or segments among rectilinear shapes. As used herein, rectilinear and generally rectilinear shapes can include “N”, “M”, “W”, “Z”, “T”, “Y”, “V”, “L”, “X” and other generally rectilinear shapes. Various embodiments of generally arcuate or generally rectilinear shapes can include shapes with both rectilinear and arcuate portions, such as a “P”, “R”, “B”, and “U”.

In order to deliver certain embodiments of the orthopedic device to a joint, various contemplated embodiments of delivery systems manipulate the shape of the orthopedic device into a less-curved, or straightened configuration. In some instances, the orthopedic device can be completely straightened, and in others the orthopedic device may be curved in an arcuate configuration that is less curved, or has a larger major diameter, than the device as fully deployed in the joint. For example, FIG. 1A shows one embodiment of an orthopedic device 100 a with substantially straight configuration. The orthopedic device 100 a has a proximal end 110 a and a distal end 120 a in relation to insertion into the body of a patient, such as into a joint. In various embodiments of orthopedic devices discussed herein, the distal end of the orthopedic device is advanced or inserted into the body of a patient first, while the proximal end of the orthopedic device is initially inserted proximal to the distal end. In various embodiments, the orthopedic device 100 a has various shape configurations to permit loading from a lumen within a needle, cannula, or other device for delivering the orthopedic device to the site for implantation. In one embodiment the straight configuration of orthopedic device 100 a is suited for delivery from a substantially straight needle. In other embodiment configurations, the orthopedic device 100 a is flexible and can be bent or biased to have a curve or other shape to permit delivery from curved or other-shaped needles or cannulae. In one embodiment the orthopedic device 100 a is delivered over a delivery structure.

As illustrated, one embodiment of the orthopedic device has a relatively consistent width of the elongate device. However, in other contemplated embodiments, the width of the device body can vary along its length. For example, the orthopedic device can have a taper along a portion of its length, or be tapered along the device's entire length. Width, or other dimension, can vary from large to small or small to large, making the device thicker in some portions than in others.

In one embodiment, the orthopedic device 100 a is made of a shape memory material. For example, the shape memory material can be made from a heat set/shaped shape-memory material, such as Nitinol or a shape memory plastic, polymeric, or synthetic material, such as polycarbonate urethane. For example, one embodiment of the orthopedic device 100 a comprises a shape memory material including a shape memory polyurethane or polyurethane-urea polymer. One example of this type of shape memory material is described in United States Patent Publication 2002/0161114 A1 entitled “Shape memory polyurethane or polyurethane-urea polymers” which is incorporated in its entirety by reference herein. Publication 2002/0161114 A1 describes a shape memory polyurethane or polyurethane-urea polymer including a reaction product of: (A) (a) silicon-based macrodiol, silicon-based macrodiamine and/or polyether of the formula (I): A—[(CH₂)_(m)—O—]_(n)—(CH₂)_(m)—A′, wherein A and A are endcapping groups; m is an integer of 6 or more; and n is an integer of 1 or greater; (b) a diisocyanate; and (c) a chain extender; or (B) (b) a diisocyanate: and (c) a chain extender, said polymer having a glass transition temperature which enables the polymer to be formed into a first shape at a temperature higher than the glass transition temperature and maintained in said first shape when the polymer is cooled to a temperature lower than the glass transition temperature, said polymer then being capable of resuming its original shape on heating to a temperature higher than the glass transition temperature. Various embodiments of the present invention relate to a shape memory polymer alone or a shape memory composition which includes a blend of two or more of the shape memory polyurethane or polyurethane-urea polymers defined above or at least one shape memory polyurethane or polyurethane-urea polymer defined above in combination with another material. The present invention further relates to processes for preparing materials having improved mechanical properties, clarity, processability, biostability and/or degradation resistance and devices or articles containing the shape memory polyurethane or polyurethane-urea polymer and/or composition defined above.

In one embodiment the orthopedic device 100 a comprises an articular layer 105, which may also be called a blanket or a jacket. The articular layer 105 is sized and configured to be placed within a body, such as in a joint as a layer between bones of the joint to provide a slideable articulation surface and/or a cushion. In one embodiment the articular layer 105 is configured to be compressed by loading in the joint. For example, in one embodiment an articular layer may be compressed from a substantially circular cross-sectional shape to an oval, elliptical, or football shaped cross-section, which further increases the amount of surface coverage of the articular layer with respect to bony joint contact, resulting in reduced pressure at the joint. In one embodiment the operating range of compression of an orthopedic device is in the range of 0 to 50% of the cross sectional diameter.

In one embodiment the articular layer is made of a shape memory material, as described above. In certain embodiments of the orthopedic device 100 a, the body of the orthopedic device 100 a consists only of an articular layer which has shape-memory properties. In other embodiments, as is described below, additional structures within the articular layer may also have shape memory characteristics. In certain embodiments, the articular layer 105 materials include but are not limited to Silicone, Teflon, Ultra High Molecular Weight Polyurethane or and any implantable grade material. In certain embodiments, the articular layer 105 can be compliant and or compressible or of a non-compressible construction. In certain embodiments, the articular layer 105 can for instance have a variety of durometers (material hardness). In certain embodiments, the articular layer 105 could also be infused with air bubbles becoming much like a sponge. In certain embodiments, the articular layer 105 can be provided in a number of shapes and be continuous or of interrupted/individual sections. In certain embodiments, the articular layer 105 may contain a material or a drug to inhibit inflammation, joint deterioration etc, or a material or drug to encourage tissue regeneration or device encapsulation. In certain embodiments the articular layer 105 comprises a cartilage replacement material or comprises a natural or synthetic cartilage.

In certain embodiments, the articular layer 105 is coated with a drug such as a long lasting steroid. In certain embodiments the articular layer is provided with wells, pockets, bubbles or capsules for drug delivery. In one embodiment the articular layer 105 is coated with a secondary surface such as another polymer of a different material property or an antifriction high wear material such as Parylene or other similar materials which are known to the art as providing for a low friction surface.

In certain embodiments, the articular layer 105 is radiopaque, providing for visibility of the device when implanted as viewed by X-Ray and/or other Fluoroscopic equipment. In one embodiment the articular layer 105 radiopacity is provided by radiopaque markers (not shown here) or by loading the articular layer 105 with platinum, gold or other biocompatible metal.

As described above, in various embodiments the orthopedic device can be an arcuate configuration once it is implanted in a joint. Some non-limiting examples of arcuate configurations include an open hoop such as is shown in the embodiment in FIG. 1B, and a nautilus-style spiral as is shown in the embodiment in FIG. 1C. Referring to FIG. 1B, the open hoop arcuate configuration embodiment of the orthopedic device 100 b has a proximal end 110 b and a distal end 120 b in relation to insertion into the body of a patient, such as into a joint. In certain embodiments orthopedic device 100 b has many similar attributes and characteristics of orthopedic device 100 a, such as shape memory and/or an articular surface 105. In certain embodiments, orthopedic device 100 b is an arcuate configuration of orthopedic device 100 a. In certain embodiments the orthopedic device of 100 a is biased to the configuration as shown for orthopedic device of 100 b. The bias may be a preferred configuration for a flexible, pliable, bendable device. In certain embodiments the orthopedic device of 100 a can change to the configuration as shown for orthopedic device of 100 b by a change in ambient or implantation site temperature or the introduction of an activating medium or material. In certain embodiments, the orthopedic device is reversibly configurable between various shapes or geometries.

In one embodiment the orthopedic device 100 b floats inside the joint to better conform to the natural movement of the bones through the range of motion of the joint. In one embodiment the “open ring,” “hoop” or “coil” configuration of orthopedic device 100 b is designed to offer a mechanical advantage over that of fixed type prosthesis as in a total joint replacement as described above in the Background section. The design allows for the distribution of the loading, shearing and/or compressive forces seen by the articulation and or loading of the joint. As the orthopedic device 100 b is not a closed hoop, it is not fixed in place (e.g. attached to either end of bones in a joint) it in effect “floats” between the ends of the bones in a joint. Thus, the orthopedic device 100 b offers little to no resistance to shape change and can spring open or closed as force is applied to the device or to the joint, but still maintain the purpose of providing a bearing, cushion, slideable, or articulate surface. As there is little to no resistance to the shape change the orthopedic device 100 b in turn allows for the distribution of the forces and/or shear as well as resulting wear along the device more equally. In various arcuate configurations, such as a open circle or continuous spiral, embodiments of the orthopedic device are not closed like a complete ring or closed circular shape would be, resulting in increased dissipation of loading and compression though at least two deformations in the orthopedic device. First, an open ring allows for dynamic loading response as force that is applied to the joint is partially dissipated by the force necessary to radially-outwardly deform the open ring or spiral into a larger radius profile. In one embodiment the operating range of radial deformation of an arcuate orthopedic device is in the range of 0 to 50% of the orthopedic device profile diameter within the joint. Second, as discussed above, the compression of the articular layer resulting in cross-sectional deformation into a flatter shape also dissipates force or pressure in the joint.

In one embodiment the orthopedic device 100 b is sized to snugly fit into the joint capsule itself. This fit maintains the orthopedic device 100 b center with respect to the axis of the bones of the joint, such as in a finger or a knuckle in one non-limiting example.

In various embodiments the orthopedic device 100 b comprises ends which are biased or bent slightly towards or away from its center (see e.g., FIGS. 5B-5C, 21A-21B). In one embodiment the orthopedic device, or coil, is out of plane on one or both ends, providing a secondary shock absorbing component to the orthopedic device as the bones in the joint are compressed axially. In one embodiment the orthopedic device 100 b is substantially flat, or planar.

One example of a nautilus-style spiral arcuate configuration is the embodiment of an orthopedic device 100 c as shown in FIG. 1C. The orthopedic device 100 c has a proximal end 110 c and a distal end 120 c in relation to insertion into the body of a patient, such as into a joint. In certain embodiments orthopedic device 100 c has many similar attributes and characteristics of orthopedic device 100 a and/or 100 b, such as shape memory and/or an articular surface 105. In certain embodiments, orthopedic device 100 b is an arcuate configuration of orthopedic device 100 a. In certain embodiments the orthopedic device of 100 a may be altered in to a configuration as shown for orthopedic device of 100 c. The bias may be a preferred configuration for a flexible, pliable, bendable device. In certain embodiments the orthopedic device of 100 a when unconstrained can change to the configuration as shown for orthopedic device of 100 c, or by a change in ambient or implantation site temperature or the introduction of an activating medium or material. In certain embodiments, the orthopedic device is reversibly configurable between various shapes or geometries.

The orthopedic device 100 c floats inside the joint to better conform to the natural movement of the bones through the range of motion of the joint. The nautilus-style spiral arcuate configuration also offers the advantages outlined by the open hoop arcuate configuration, or hoop configuration, but provides a larger bearing surface to the joint. With the extended length of the spiral configuration, the orthopedic device 100 c is configured to provide more of an articulate surface, resulting in decreased pressure on the bones by dissipating forces over a larger surface area. The cross sectional diameter multiplied by the number of winds in a spiral shape roughly equals the surface area coverage of the articular surface in conformation with the bones of the joint. For example, a small cross sectional diameter of a spiral configuration allows for a plurality of windings in the spiral. This plurality of spiral windings can then adjust to the general surface area of either bone as the joint articulates.

As described thus far, certain descriptions of embodiments of orthopedic devices have focused on the outside of the device. However, the inside of the devices can have additional structure. For example, in FIG. 2 an orthopedic device 200 according to one embodiment of the present invention comprises an elongate core 240 and an articular layer 230 surrounding at least a portion of the core 240. Referring back to FIGS. 1A-1C, various embodiments of orthopedic devices 100 a, 100 b and/or 100 c can either have an elongate core or lack an elongate core. In other embodiments of orthopedic devices 100 a, 100 b and/or 100 c can either have an articular layer or lack an articular layer. In other words, the orthopedic device may consist of an elongate core, an articular layer, or both.

As illustrated in the embodiment of at least FIG. 2 the orthopedic device 200 includes the elongate core 240 in addition to the articular layer 230. One preferred embodiment of the orthopedic device 200 includes an elongate core 240 and an articular layer 230 wherein one or both the elongate core 240 and the articular layer 230 comprise a shape set memory material. In some embodiments the articular layer 230 can surround or encapsulate the entire elongate core 240. In other embodiments the articular layer 230 surrounds, encapsulates, encloses or covers at least a portion of the core 240. As used herein, “surround,” “encapsulate” and “enclose” include configurations in which a core is not completely surrounded, completely encapsulated or completely enclosed. For example, certain embodiments of an orthopedic device contemplate an articular layer which “surrounds” an elongate core with a continuous or non-continuous helical band, discontinuous tabs, or other intermittent articular layer structure.

In one embodiment the articular layer 230 is similar to any articular layer described herein. Likewise, in various embodiments, any articular layer may have some or all of the features of other articular layer embodiments described herein.

In one embodiment the elongate core 240 comprises a shape memory material. For example, the elongate core 240 can comprise a shape memory material can made from a heat set/shaped shape-memory material, such as Nitinol or a shape memory plastic, polymeric, synthetic material. For example, one embodiment of the elongate core 240 comprises a shape memory material including a shape memory polyurethane or polyurethane-urea polymer, as is described above. In one embodiment the elongate core 240 comprises a metal “open” ring such as Nitinol encapsulated by an articular layer 230, or outer blanket, comprising silicone. In one embodiment the elongate core 240 comprises a hardened polymer. In one embodiment the elongate core 240 is configured such that a heat set Nitinol with an arcuate configuration, such as an open ring configuration, a horseshoe configuration, or a spiral configuration, can be straightened for delivery through cooling or plastic deformation, then recovered to its original heat-set shape once released from a delivery system, such as one embodiment using a properly sized hypodermic needle. In one embodiment the elongate core 240 comprises a non-shape memory material which can be bent or deformed.

In certain embodiments, the elongate core 240 is coated or impregnated with a drug such as a long lasting steroid. In one embodiment the elongate core 240 is coated with a secondary surface such as another polymer of a different material property or an antifriction high wear material such as Parylene or other similar materials which are known to the art as providing for a low friction surface.

In one embodiment an orthopedic device comprises a removable elongate core and an articular layer. The removable elongate core can be any among the various elongate cores described herein. The orthopedic device would be inserted with an elongate core within the orthopedic device to keep the orthopedic device in a rigid substantially-straight or arcuate shape configuration. When placed in a target site such as a joint in a patient, the removable elongate core could be removed leaving the articular layer in place at the target site. In one embodiment the lumen left in the articular layer by the removal of the elongate core remains hollow allowing for compression, deformation, or cushioning of the joint by the orthopedic device's articular layer (see discussion relating to FIG. 18 below). This lumen, or center, could also be filled with a lumen material such as a liquid, polymer, collagen, or drug etc. The orthopedic device could be provided with a port or a valve at one or both ends to contain the lumen material. In one embodiment the lumen material is a liquid that can be configured, organized or hardened by the application of energy, radio frequency, laser, heat, cold, etc.

The cross-section of some embodiments of orthopedic devices including an elongate core can have various non-limiting options, as are shown in FIGS. 3A-3E. FIG. 3A is a schematic cross-section of an orthopedic device 300 a comprising a substantially straight configuration. In this embodiment the device comprises an elongate core 340 a and an articular layer 330 a surrounding at least a portion of the core 340 a. The articular layer 330 a has a proximal end 331 a and a distal end 332 a. The elongate core 340 a has a proximal end 341 a and a distal end 342 a 342 a. In one embodiment the orthopedic device 300 a is similar to the orthopedic device 100 a described above. FIG. 3B shows a device an elongate core 340 b and an articular layer 330 b surrounding at least a portion of the core 340 b in an open hoop arcuate configuration. The articular layer 330 b has a proximal end 331 b and a distal end 332 b. The elongate core 340 b has a proximal end 341 b and a distal end 342 b. In one embodiment the orthopedic device 300 b is similar to the orthopedic device 100 b described above. Certain embodiments of a spiral shaped device, such as is shown in FIG. 3C can have a single elongate core. For example, orthopedic device 300 c comprises a nautilus-style spiral arcuate configuration, the device comprising an elongate core 340 c and an articular layer 330 c surrounding at least a portion of the core 340 c. The articular layer 330 c has a proximal end 331 c and a distal end 332 c. The elongate core 340 c has a proximal end 341 c and a distal end 342 c. In one embodiment the orthopedic device 300 c is similar to the orthopedic device 100 c described above.

In some embodiments, the elongate core can wrap around on itself or consist of a number of pieces, such as is shown in FIGS. 3D and 3E. FIG. 3D shows an orthopedic device 300 d with an open hoop arcuate configuration. The device 300 d comprises one or more elongate cores 340 d wrapped, braided or folded along a length of the device and an articular layer 330 d surrounding at least a portion of the core(s) 340 d. The articular layer 330 d has a proximal end 331 d and a distal end 332 d. The elongate core 340 d has a proximal end 341 d and a distal end 342 d. In one embodiment the orthopedic device 300 d is similar to the orthopedic device 100 b described above. In the illustrated embodiment in FIG. 3D, the elongate core 340 d is a unitary body. In other embodiments, two or more elongate cores 340 d are situated in a roughly parallel or co-linear orientation, which can be twisted or braided or interlocked. Other embodiments of the orthopedic device need not be limited to a single elongate core or backbone, but could have a plurality of cores or backbones including a braided configuration, continuous overlaps, etc. FIG. 3E shows an orthopedic device 300 e with a nautilus-style spiral arcuate configuration. The device 300 e comprises one or more elongate cores 340 e wrapped or folded along a length of the device and an articular layer 330 e surrounding at least a portion of the core(s) 340 e. In the illustrated embodiment in FIG. 3E, the elongate core 340 e is a unitary body. In other embodiments, two or more elongate cores 340 e are situated in a roughly parallel or co-linear orientation, which can be twisted or braided or interlocked. Other embodiments of the orthopedic device need not be limited to a single elongate core or backbone, but could have a plurality of cores or backbones including a braided configuration, continuous overlaps, etc.

The shape of the elongate core can vary, as is shown in embodiments in FIGS. 4A-4C. FIG. 4A shows an elongate core 440 a with one or more substantially linear or straight members. FIG. 4B shows an elongate core 440 b with one or more wave, curve or zig-zag members that may be in one or more planes at any angle with respect to one another. FIG. 4C shows an elongate core 440 c with one or more members in a braided or weave configuration. Any of these patterns can be used with any of the elongate cores disclosed herein.

Various embodiments of elongate cores can have different features along the length or ends of the core, as is shown in FIGS. 5A-5C. An elongate core 540 a with an open hoop arcuate configuration can have one or more end segments, as is shown in FIG. 5A. Such end segments can include proximal end segment 561 a and/or distal end segment 562 a. In various embodiments, the elongate core or cores 540 a can have zero, one, two or more end segments. In one embodiment the end segment 561 a or 562 a is radiopaque or can be used as a marker for visualization of the ends of the orthopedic device. The elongate core 540 a has a proximal end 541 a and a distal end 542 a. In one embodiment the end segments 561 a and 562 a are spherical bodies. In another embodiment, the end segments 561 a and 562 a are loops. In one embodiment the end segments 561 a and 562 a extend from the same material as the length of the elongate core 540 a. In one embodiment the end segments 561 a and 562 a are separate elements made of the same or different material as the length of the elongate core 540 a and which are bonded, fused, welded, glued, or otherwise attached to the proximal end 541 a and a distal end 542 a, respectively. Although not illustrated, it is contemplated that an elongate core 540 a has one or more medial segments anywhere along the length of the elongate core 540 a. In various embodiments, elongate core 540 a has end segments or medial segments to help improve stability of an articular layer or outer blanket, and need not be flat or planar, but can be biased out of the primary plane of the device at one end or both ends.

One elongate core 540 b embodiment includes one or more bends, such as proximal bend 541 b and/or distal bend 542 b as shown in FIG. 5B. In various embodiments, the bends can also be called hooks. In various embodiments, the bends or hooks can be closed off to form a loop, as with certain embodiments of elongate core 540 a. Alternately, elongate core 540 c has one or more segments bent in or out of the primary plane of the device as shown in FIG. 5C. In one embodiment proximal segment 541 c is bent radially inward from the curvature of the elongate core 540 c. In one embodiment distal segment 542 c is bent radially outward from the curvature of the elongate core 540 c. In other embodiments, proximal segment 541 c and/or distal segment 542 c are bent radially inward, radially outward, and/or up or down from the primary plane of the elongate core 540 c.

Elongate cores can have any of a variety of cross-sectional structures or profiles. For example, some embodiments of elongate cores cross-sections are shown in FIGS. 6A-6K. The illustrated embodiments are not limiting, but merely examples of various possible cross-sectional profiles of any of the embodiments of elongate cores or orthopedic devices described herein. The illustrated embodiments shows a variety of possible cross-sectional shapes for embodiments of the device or the core of the device, including a square, ellipse, triangular, etc., and wherein the elongate core can be modified by twisting, abrading, pitting and zigzagging, etc.

FIG. 6A illustrates a cross-sectional view of an embodiment of a circular profile elongate core 640 a, which can be rotated along a longitudinal axis of the core 640 a. In various embodiments the elongate core 640 a is at least partially surrounded by an articular layer, wherein the elongate core 640 a and/or the articular layer actuate between a straight or slightly curved configuration to a more curved or arcuate configuration. During this change in configuration, elongate core 640 a and the articular layer may rotate with respect to each other. In one embodiment the elongate core 640 a and the articular layer has some frictional engagement, which may interfere with rotation between the elements, resulting in some level of deformation. Furthermore, in one embodiment both the elongate core 640 a and the articular layer will have different material properties which are dependent on stiffness, durometer and other aspects of the respective materials. Depending on the desired orientation of an orthopedic device during delivery to a joint, the orientation of the elongate core 640 a and/or the articular layer may be controlled by the configuration of the delivery device being used.

In various embodiments, an elongate core may be configured to limit deformation and/or rotation in various orientations during a change in configuration between straightened and curved profiles. FIG. 6B illustrates a cross-sectional view of an embodiment of a triangular profile elongate core 640 b, which can limit rotation of an articular layer along a longitudinal axis of the core 640 b. FIG. 6C illustrates a cross-sectional view of an embodiment of a rectangular profile elongate core 640 c, which can limit rotation of an articular layer a longitudinal axis of the core 640 c. FIG. 6D illustrates a cross-sectional view of an embodiment of a trapezoidal profile elongate core 640 d, which can limit rotation of an articular layer along a longitudinal axis of the core 640 d. FIG. 6E illustrates a cross-sectional view of an embodiment of an oval or elliptical profile elongate core 640 e, which can limit rotation of an articular layer along a longitudinal axis of the core 640 e. FIG. 6F illustrates a cross-sectional view of an embodiment of a ridged profile elongate core 640 f, which can limit rotation of an articular layer along a longitudinal axis of the core 640 f. FIG. 6G illustrates a cross-sectional view of an embodiment of a non-symmetric profile elongate core 640 g, which can limit rotation of an articular layer along a longitudinal axis of the core 640 g. FIG. 6H illustrates a cross-sectional view of an embodiment of a cross or X-profile elongate core 640 h, which can limit rotation of an articular layer along a longitudinal axis of the core 640 h. FIG. 6I illustrates a cross-sectional view of an embodiment of a lumen profile elongate core 640 i, which can limit rotation of an articular layer along a longitudinal axis of the core 640 i. FIG. 6J illustrates a cross-sectional view of an embodiment of a pentagon profile elongate core 640 j, which can limit rotation of an articular layer along a longitudinal axis of the core 640 j. FIG. 6K illustrates a cross-sectional view of an embodiment of a hexagon profile elongate core 640 k, which can limit rotation of an articular layer along a longitudinal axis of the core 640 k.

Some embodiments of an elongate core include a plurality of interconnectable discrete elongate members, such as is shown in FIGS. 7-9C. In various embodiments, two or more discrete elongate members may be connected along a single core wire, a series of core wires, or connectors. In one embodiment one or more discrete elongate members can rotate or spin about the connector or core wire. In another embodiment one or more discrete elongate members are affixed to the connectors or core wire in a manner to reduce or prevent rotation of the elongate members with respect to connector or core wire. As illustrated in FIG. 7A one embodiment of an orthopedic device 740 a comprising a plurality of interconnectable discrete elongate members has elongate members 742, 744 and 746 which are linked by connector 760. In various embodiments the connector 760 can be a single core member extending between all the discrete elongate members, or it can be any number of discrete connecting members between the elongate members. In one embodiment, an orthopedic device 740 b with a plurality of independent or interconnectable discrete elongate members can have a “W”-shaped generally rectilinear configuration. The connectors 760 can be configured to orient the elongate members such as 742, 744, 746 and 748 in any number of orientations or angles. In various embodiments the connectors 760 can have shape memory configurations or biases for particular orientations depending on the doctor's preference or the device selected. The overall shape of an orthopedic device can have any number of configurations: for example, at least a “C”, “O” and “W” shape have been mentioned, but the device and/or articular layer and/or elongate core can be in any shape or configuration. The device is not limited to the “C”-shape or a spiral shape.

An elongate core may comprise a plurality of discrete members of one of various shapes and sizes, wherein the discrete members may be interconnected to function as an elongate core or a backbone as set forth herein. Likewise, FIG. 8 shows orthopedic device 840 with interconnected members 841, 842, and 843 which are linked by an extendable connector 860.

One embodiment of an elongate core 940 a with a plurality of interconnectable discrete members, or links 950 a, in a substantially straight configuration is shown in FIG. 9A. Elongate core 940 a may be described as a multi-link elongate core, multi-link core, multi-link orthopedic device, or multi-link orthopedic implant. In one embodiment of a multi-link orthopedic device a series of rigid or flexible links are configured to translate the multi-link core from a straight or slightly curved configuration into a curved orientation or configuration. The diameter of curvature of the device could be adjustable by the ratcheting features provided on each link 950 a. In one embodiment the links 950 a are made of a material that can undergo some level of elastic deformation. In another embodiment, the links 950 a are made of a more rigid material. With embodiments of the device, core, or link that are made from a super elastic material such as Nitinol, the implant can be straightened from its curved, deployed or implanted configuration and placed in a needle or cannula. However, a less elastic material such as stainless steel or certain plastics might yield or break if straightened that much. Using a curved delivery system, such as one shown in FIG. 10C below, would allow a more-rigid arcuate implant to be slightly straightened enough for insertion, but not enough to cause yielding.

Looking closer at a link, FIG. 9B shows a side view of one link 950 b. In one embodiment link 950 b is a link 950 a of FIG. 9A. In one embodiment link 950 b comprises a first end 951 and a second end 952. Various links 950 b are interconnectable between the second end 952 of a first link 950 b and the first end 951 of a second link 950 b′, and in one embodiment the interconnection is a hinged connection between a first link interface 990 and a second link interface 980. In one embodiment the first link interface 990 is a post and the second link interface 980 is a channel in which the post is captured to allow rotation. In another embodiment, the second link interface 980 is a post and the first link interface 990 is a channel in which the post is captured to allow rotation. In various other embodiments, other link interfaces allowing some rotation including snap fits, connectors, or other similar interfaces may be used. In the illustrated embodiment, the link 950 b comprises a ratchet prong 960 and ratchet teeth 970. The ratchet teeth 970 of one link 950 b interact with the ratchet prong 960 of a second link 950 b′ to allow rotation with respect to links 950 b and 950 b′ while restricting or limiting rotation in the opposite direction.

Various link embodiments can be configured to an arcuate configuration, as in FIG. 9C showing an elongate core 940 c with links according to FIG. 9A in an arcuate open loop configuration. In one embodiment the elongate core 940 c is actuated and locked into an arcuate configuration by the ratcheting mechanism as described above. In one embodiment the ratchet locking is configured to be disengageable such that the prong is releasable from the teeth to allow the elongate core 940 c to rotate in a straight or less-curved configuration.

2. Method and Apparatus for Delivering Implantable Orthopedic Devices

In various embodiments of orthopedic devices described herein, the orthopedic devices are configured to have an arcuate shape in a joint. In certain embodiments, the orthopedic device can be straightened into a substantially straight or less-curved configuration for implantation with an orthopedic device delivery system. For example, in one embodiment an arcuate orthopedic device can be straightened by cooling or chilling a shape-memory material in the orthopedic device and then inserting the orthopedic device into a tube, cannula, or hypodermic needle of specific design shape and cross section. The pre-loaded hypodermic needle is then attached to a handle through a coupling or interface such as a luer lock standard to the industry or any other attachment means. The physician then straightens the finger by applying force providing for a space or gap to occur in the joint. For example, the force can be provided by using his hands, or a tool, to pull, stretch or spread the desired joint. In one embodiment a sharp tool such as a scalpel or trocar can be used to pierce the joint tissue. In another embodiment, the deliver device needle can pierce the joint tissue. The needle is positioned mid-point between the posterior and anterior surfaces of the joint. The tip of the needle is advanced into the joint, completely within the joint capsule. Once inserted the physician releases the device by advancing it out of the needle using an advancing mechanism, such as a handle and plunger. Once deployed the needle and handle can be removed from the joint. If more than one joint, such as a knuckle, is treated the deployed needle can be removed via the luer type connector and a second attached to the same handle, repeating the procedure as needed.

One orthopedic device delivery system 1000 comprising a handle 1010 and a plunger 1020 that is suitable for delivering the orthopedic device implant is shown in FIG. 10A. In various embodiments, the orthopedic device delivery system 1000 can be provided in a number of mechanical configurations. One objective of the orthopedic device delivery system 1000 is to completely advance the orthopedic device out of a channel, cannula, lumen, or needle, with non-limiting examples illustrated in FIGS. 10B and 10C. In various embodiments, the orthopedic device delivery system 1000 is actuated by advancing the orthopedic device by a simple ram type piston or hypodermic needle configuration, or through the use of a lead screw, or through the use of a pneumatic or hydraulic type mechanism. In the illustrated embodiment, the handle 1010 comprises a distal handle region 1012 and a proximal handle region 1011 and the plunger 1020 comprises a distal plunger region 1022 and a proximal plunger region 1021. In one embodiment the distal handle region 1012 comprises a cannula interface 1015, such as a luer connector.

Embodiments of a cannula or needle can be straight or curved, as in FIGS. 10B and 10C respectively. A substantially straight cannula 1030 b or needle with a lumen 1035 b is suitable for delivering the orthopedic device implant described herein in conjunction with the orthopedic device delivery system 1000 of FIG. 10A. In one embodiment the cannula 1030 b comprises a distal cannula region 1032 b and a proximal cannula region 1031 b. In one embodiment the delivery cannula 1030 b can be attached to a handle 1010 in an orthopedic device delivery system such as orthopedic device delivery system 1000 with any of a number of attachment means such as a standard luer type coupler, bayonet, a luer mount, or a thread type means for attachment to the delivery handle 1010. In one embodiment proximal cannula region 1031 b comprises a flange 1038 b and a luer connector 1037 b. The needle or deployment cannula 1030 b can be provided in many shapes and cross sections. In one embodiment the cannula 1030 b is sized and configured to interface with the orthopedic device in a specific orientation for delivery into a joint. This interface may be a key-slot, or other mechanical interface. In one embodiment the distal cannula region 1032 b is provided at its distal end with an insertion feature such as a point, knife edge or blunt atraumatic edge.

Another embodiment of orthopedic device delivery system comprising an arcuate cannula 1030 c or curved needle is shown in FIG. 10C. It has a lumen 1035 c is suitable for delivering the orthopedic device implant described herein in conjunction with the orthopedic device delivery system 1000 of FIG. 10A. In various embodiments, arcuate cannula 1030 c is similar to substantially straight cannula 1030 b, except that arcuate cannula 1030 c is more curved. In one embodiment the cannula 1030 c comprises a distal cannula region 1032 c and a proximal cannula region 1031 c. In one embodiment the delivery cannula 1030 c can be attached to a handle 1010 in an orthopedic device delivery system such as orthopedic device delivery system 1000 with any of a number of attachment means such as a standard luer type coupler, bayonet, a luer mount, or a thread type means for attachment to the delivery handle 1010. In one embodiment proximal cannula region 1031 c comprises a flange 1038 c and a luer connector 1037 c. The needle or deployment cannula 1030 c can be provided in many shapes and cross sections. In one embodiment the cannula 1030 c is sized and configured to interface with the orthopedic device in a specific orientation for delivery into a joint. This interface may be a key-slot, or other mechanical interface. In one embodiment the distal cannula region 1032 c is provided at its distal end with an insertion feature such as a point, knife edge or blunt atraumatic edge.

In some embodiments the process or method of inserting an orthopedic device into a joint is preferably atraumatic. In one embodiment a fluoroscopically placed stab incision is followed by a cannula insertion for orthopedic device delivery. The stab incision would by its nature provide a path for a delivery needle or cannula to follow. The stab incision could or would remove the necessity for the cannula tip to be sharp. For example, In one embodiment a joint such as a knuckle can be physically identified for orthopedic device placement. The device can be fluoroscopically placed or inserted without fluoroscopy. A cannula is inserted into the stab incision and the orthopedic device is delivered through the cannula in the incision to the joint.

Looking more closely at the tip of a needle or cannula, FIGS. 10D and 10E illustrate two potential options. A blunted delivery cannula 1030 d with a lumen 1035 d is shown in FIG. 10D. In certain embodiments, the blunted delivery cannula 1030 d is used in conjunction with a joint piercing tool (not illustrated here) such as a knife, scalpel, spike, trocar, or other sharp instrument for piercing tissue surrounding a joint in order to create an access hole or port through which a cannula can be inserted to provide the orthopedic device access to a joint. An angular tip 1030 e with a lumen 1035 e is shown in FIG. 10E. In one embodiment the angular tip 1030 e is sharp enough to pierce tissue surrounding a joint in order to create an access hole or port through which a cannula can be inserted to provide the orthopedic device access to a joint. In another embodiment, the angular tip 1030 e is atraumatic and is used to guide the delivery device in a previously opened incision or natural opening in tissue. Minimally or atraumatic distal cannula regions 1032 b, 1032 c corresponding to any cannula, such as cannula 1030 b-E are intended to be slid through the stab incision, such as made by a scalpel, thereby spreading the tissue which makes up the knuckle capsule as it goes in.

As described above, in various embodiments an elongate core is at least partially surrounded by an articular layer, wherein the elongate core and/or the articular layer actuate between a straight or slightly curved configuration to a more curved or arcuate configuration. During this change in configuration, elongate core and the articular layer may rotate with respect to each other. In one embodiment the elongate core and the articular layer has some frictional engagement, which may interfere with rotation between the elements, resulting in some level of deformation. Furthermore, in one embodiment both the elongate core and the articular layer will have different material properties which are dependent on stiffness, durometer and other aspects of the respective materials. Depending on the desired orientation of an orthopedic device during delivery to a joint, the orientation of the elongate core and/or the articular layer may be controlled by the configuration of the delivery device being used. In various embodiments, the shape, curvature, or tip of the cannula, needle, or lumen can be configured to control the specific orientation of the orthopedic device as it is being implanted. For instance, the point of a needle, trocar, or angle-tipped cannula such as an orthopedic device delivery system with an angular tip 1030 e could be used to define the relationship of the orthopedic device and its orientation in a joint.

One way of delivering embodiments of the orthopedic device is shown in FIG. 11, where an implantable orthopedic device 1100 is advanced through a cannula 1110 by a plunger 1120. The orthopedic device 1100 comprises a distal end 1102 and a proximal end 1101, and is similar to the embodiments of orthopedic devices described herein. The cannula 1110 has a distal end 1112 which is configured to present the orthopedic device 1100 into the implant delivery site in a joint in the proper orientation. The plunger 1120 has a distal end 1122 which advances the orthopedic device 1100 out of the cannula 1110 and into the joint. In the illustrated embodiment, the distal end 1122 of the plunger 1120 pushes the proximal end 1101 of the orthopedic device 1100. In one embodiment the plunger is sized to match the cross sectional diameter of the proximal end of the device and can also be provided with features to engage the device in a specific fashion. In other embodiments (not illustrated) the plunger is configured to attach to a distal or medial portion of the orthopedic device to pull or advance the device out of the cannula. In one embodiment the orthopedic device delivery system is configured to deliver the orthopedic device 1100 in an orientation within a plane (“primary plane”) roughly corresponding to a plane of bony or cartilaginous articulation within a joint, which is roughly orthogonal to a longitudinal axis of at least one bone comprising part of the joint. As an orthopedic device is delivered into a joint, such as a knuckle, the tissue surrounding the knuckle including a joint capsule and various ligaments helps maintain the orientation of the orthopedic device in or near the primary plane within the joint by containing the orthopedic device around its outer periphery. In one embodiment an angular tip at the distal end 1112 of the cannula 1110 helps maintain the proper orientation of the orthopedic device 1100 within or near the primary plane and avoiding undesired bias or deformation of the orthopedic device 1100.

Some of the steps in delivering an orthopedic device 1200 in a joint with an orthopedic device delivery system are illustrated in FIGS. 12A-15B. In these figures a joint comprises a first bone 1201, a second bone 1202, and tissue 1203 surrounding the joint, such as a joint capsule and/or a ligament. The “A” figures illustrate a side view of the joint and the “B” figures illustrate a cross-sectional view orthogonal to the side view in “A.” The primary plane of the orthopedic device roughly corresponds to the plane of the “B” when bones 1201 and 1202 are roughly linear. When the bones 1201 and 1202 actuate with respect to each other, the primary plane may actuate as well to roughly correspond to a plane normal to a point of contact between the bones 1201 and 1202 with the orthopedic device 1200. A cannula 1230 with a distal end 1232 and a lumen 1235 is shown in both views. In the illustrated embodiment, the distal end 1232 of the cannula 1230 comprises a feature which helps maintain the proper orientation of the orthopedic device during delivery. As shown, one embodiment of the distal end 1232 feature is an angled tip. In each of FIGS. 12B, 13B, 14B and 15B, two embodiments of a cannula 1230 b and 1230 c are illustrated. One would be used at a time, but both are illustrated (with cannula 1230 b in solid lines and 1230 c in dotted lines) to demonstrate that a straight or curved cannula, respectively, can be used to deliver the orthopedic device as described with respect to FIGS. 10B and 10C above. A plunger 1250 advances the orthopedic device 1200 into the joint using any of the advancing mechanisms described herein.

A step showing the device prior to implantation is shown in FIGS. 12A-12B. This illustration shows both a substantially straight cannula 1230 b and another embodiment comprising an arcuate cannula 1230 c. A step illustrating at least partial insertion of the orthopedic device 1200 into the joint is shown in FIGS. 13A-13B. In one embodiment a tool (not illustrated) is used to pierce the tissue 1203 with a stab incision prior to insertion of the cannula 1230. In another embodiment, the cannula 1230 pierces the tissue 1203. The plunger 1250 advances the orthopedic device 1200 into the joint. Deployment of the device into the joint is shown in FIGS. 14A-14B. The orthopedic device 1200 is shown in an arcuate configuration. The deployment of the orthopedic device 1200 into the joint and removal of the delivery cannula(e) 1230 b or 1230 c is illustrated in FIGS. 15A-15B.

Other embodiments of orthopedic devices can have additional features which can control the extent to which a device is open or closed. For example, one orthopedic device 1600 comprising a tether 1610 and a loop structure 1620 is shown in a substantially straight configuration in FIG. 16A. In one embodiment, the orthopedic device 1600 exhibits similar characteristics as the previously described devices discussed herein. For example, the straight configuration of the device 1600 may correspond to a configuration used for device delivery. In a normal state, the device 1600 may be an open ring, arcuate shape, or other configuration or shape when it is not being straightened for delivery or removal. The orthopedic device 1600 comprises a proximal end 1601 and a distal end 1602. The proximal end 1601 comprises the tether 1610 and a distal end 1602 comprises the loop structure 1620. The tether 1610 can be a lanyard, suture, wire, or other structure which in one embodiment is unitary with the orthopedic device 1600. In one embodiment the tether 1610 is unitary with an elongate core in the orthopedic device 1600. The tether 1610 passes through the loop structure 1620. After the orthopedic device 1600 is deployed in a joint it assumes an arcuate configuration as shown in FIG. 16B. In one embodiment the tether 1610 b is pulled tight to bring the proximal end 1601 and distal end 1602 of the orthopedic device 1600 toward each other and the tether 1610 b is tied into a knot, plug, mechanical fastener or other securing mechanism 1630 b to form a substantially closed ring configuration for the orthopedic device 1600 b. Depending on the degree of desired openness in the arcuate configuration of the orthopedic device 1600, the tether 1610 b can be pulled and locked at different lengths to create a desired hoop or device size. Once the desired size is attained, the securing mechanism 1630 b is locked. The tether 1600 b can then be cut proximate to the proximal side of the securing mechanism 1630 b. The tether 1600 b can also be cut for retrieval of the device from the joint. In another embodiment an orthopedic device 1600 c comprises one or more tethers, such as tethers 1610 c and 1612 c as shown in FIG. 16C. In one embodiment the tethers 1610 c and 1612 c are secured to each other with a securing mechanism 1630 c such as is described with respect to securing mechanism 1630 b. The tethers 1610 c and 1612 c can then be cut proximate to the proximal side of the securing mechanism 1630 c. The tether 1610 c and/or 1612 c can also be cut for retrieval of the device from the joint.

Another embodiment of an orthopedic device 1700 includes a looped arcuate configuration 1710 and at least one anchor, as is shown in FIG. 17. The orthopedic device 1700 has a proximal end 1701 and a distal end 1702. In one embodiment the proximal end 1701 and distal end 1702 are crossing ends on substantially the same axis. In one embodiment the orthopedic device 1700 has a proximal anchor 1720 at the proximal end 1701 and a distal anchor 1730 the distal end 1702. Orthopedic device 1700 has a substantially straight or less-curved configuration (not illustrated) for delivery. Once the orthopedic device 1700 is delivered to the joint, it reverts to its looped arcuate configuration 1710. In various embodiments, the anchors 1720 and 1730 are unitary and formed with an elongate core in the orthopedic device 1700, are unitary and formed with the an articular layer in the orthopedic device 1700, or are formed of separate elements and attached to the orthopedic device 1700. In various embodiments the anchors 1720 and/or 1730 are threaded, tapered, cylindrical, barbed, hooks, ribs, dissolvable, drug eluting and/or non-symmetric. In one embodiment the anchors 1720 and/or 1730 are roughly cylindrical and configured to be releasably attachable with a tool or plunger. In one embodiment the anchors 1720 and/or 1730 are impregnated with a bonding material. In one embodiment the anchors 1720 and/or 1730 are secured in to tissue surrounding or in the joint, such as bone, cartilage, a capsule or ligaments. In one embodiment the anchors 1720 and/or 1730 are bio-absorbable into surrounding tissue.

Retrieval of orthopedic devices is also contemplated. For example, one orthopedic device delivery and retrieval system 1801 can grab an implantable orthopedic device 1800 and pull it through a cannula 1830 using a snare 1850, as is illustrated in FIG. 18. Orthopedic device delivery and retrieval system 1801 is configured to deploy and/or retrieve the implantable orthopedic device 1800. In one embodiment the cannula 1830 is part of a separate retrieval system with a lumen sufficiently sized and configured to recapture and retrieve a deployed orthopedic device 1800. In various embodiments the orthopedic device 1800 has end segments or medial segments along the orthopedic device 1800 articulate layer and/or elongate core, such as is illustrated in FIGS. 5A-5C. In one embodiment the orthopedic device 1800 comprises one or more snare interface points such as end segments 561 a and 562 a described with respect to FIGS. 5A-5B above. For example, end segments 561 a and 562 a can be a ball, sphere, bead, hook, loop or other feature which can be ensnared by a tightened snare 1850 to pull the orthopedic device 1800 out of the joint. In one embodiment the snare interface point is radiopaque or has markers for fluoroscopic visualization during the retrieval procedure. In one embodiment the snare 1850 is attached (not illustrated) to a handle or control device proximal to the cannula 1830. For example in one embodiment the snare 1850 is attached to a handle or plunger with can be withdrawn or pulled with respect to the cannula 1830 to tighten the snare 1850 and pull the orthopedic device out of the joint and out of the patient's body.

In one embodiment of an orthopedic device retrieval system 1801 the distal end of the cannula 1830 comprises a hook (not illustrated) which can be used to grab or retrieve an orthopedic device. In one embodiment the cannula hook is actuatable by the doctor by pressing a button to extend or rotate the hook into the joint, which then connects or grabs a part of the orthopedic device for retrieval. In an additional embodiment, the button can be released to pull the hook back into place to lock on to the orthopedic device to be recaptured. In one embodiment of an orthopedic device retrieval system 1801 only an elongate core is retrieved, leaving the articular layer in the joint in a manner similar to that discussed above regarding FIG. 2.

Another orthopedic device retrieval system 1901 can retrieve an implantable orthopedic device 1900 with a plunger 1950 connectable with a device interface 1910, as is shown in FIGS. 19A-19B. In one embodiment the device interface 1910 is a junction with a male threaded section 1911 on the distal end of the plunger 1950 and a female threaded section 1912 on the proximal end of the orthopedic device 1900. In one non-illustrated embodiment the device interface 1910 is a junction with a female threaded section 1912 on the distal end of the plunger 1950 and a male threaded section 1911 on the proximal end of the orthopedic device 1900. In one embodiment the minor diameter of the threads of the male threaded section 1911 is roughly the same as the outer diameter of the plunger or orthopedic device. In one embodiment the major diameter of the threads of the male threaded section 1911 b is less than the outer diameter of the plunger or orthopedic device resulting in a step at 1911 b to provide uniform contact with the orthopedic device 1900.

Another orthopedic device retrieval system can remove an implantable orthopedic device 2000 using a plunger 2050 connectable with a device interface 2010, as is shown in FIGS. 20A-20C. In one embodiment the device interface 2010 is a junction with closed jaws 2052 a at a distal end of the plunger 2050 and a jaw interface 2002 on the proximal end of the orthopedic device 2000. In one embodiment the jaw interface 2002 comprises a step 2005 for grasping or locking on to the jaw interface 2002. The step 2005 can be a linear, circumferential, or other feature for grasping with the jaws. In various embodiments the jaw interface 2002 comprises a portion of an articular layer 2003, a portion of an elongate core 2004, or, as illustrated in FIG. 20C, both a portion of an articular layer 2003 and a portion of an elongate core 2004 according to various embodiments of elongate cores and articular layers described herein. In one embodiment with the jaw interface 2002 comprising a portion of the elongate core 2004, the elongate core 2004 is exposed at the jaw interface 2002. The closed jaws 2052 a can be actuated into open jaws 2052 b to release the orthopedic device 2000 into a joint. Conversely, the open jaws 2052 b can be actuated into a closed configuration as closed jaws 2052 a to recapture the orthopedic device 2000 from the joint. In one embodiment jaws 2052 a and 2052 b are spring loaded. In alternative embodiments, the device interface 2010 comprises a solenoid, linkage, ring mechanism, push-pin, snap-fit, and ball-detent interface. In one embodiment the device interface 2010 is an electrolyte junction whereby the application of energy, such as electricity, causes the junction to dissolve thereby breaking the junction between the plunger 2050 and the orthopedic device 2000.

FIGS. 21A-21C illustrate non-limiting embodiments of orthopedic devices which may exhibit similar characteristics of other orthopedic devices described above. FIGS. 21A and 21B illustrate orthopedic devices 2100 a and 2100 b, respectively, which have a multi-planar configuration which may be similar to the devices illustrated in FIGS. 1C and 1B or FIG. 3C or 3B. Here, the devices show a characteristic demonstrating that the devices do not have to be constrained in a single plane. FIG. 21C is a schematic side view of an orthopedic device 2100 c according to one embodiment of the present invention comprising a “W”-shaped generally rectilinear configuration. This embodiment further demonstrates devices that are not limited to arcuate configurations.

It will be understood that the foregoing is only illustrative of the principles of the invention, and that various modifications, alterations, and combinations can be made by those skilled in the art without departing from the scope and spirit of the invention. Accordingly, it is not intended that the invention be limited, except as by the appended claims. 

1. An orthopedic device suitable for minimally invasive deployment using a tubular delivery apparatus, the orthopedic device comprising an elongate core having a proximal end and a distal end, the core comprising a generally arcuate configuration at substantially body temperatures to enhance self-centering positioning of the orthopedic device when deployed, said core being manipulatable into a substantially straight configuration to permit delivery.
 2. The orthopedic device of claim 1, further comprising an articular layer surrounding at least a portion of the core.
 3. The orthopedic device of claim 1, wherein the core comprises shape memory material.
 4. The orthopedic device of claim 1, wherein the generally arcuate configuration comprises a spiral shape.
 5. The orthopedic device of claim 1, wherein the core, when in a generally arcuate configuration, is substantially non-planar.
 6. The orthopedic device of claim 2, wherein the device is further configured to permit at least partial removal of at least part of the core from the articular layer resulting in a void within the articular layer.
 7. The orthopedic device of claim 6, wherein the device is further configured so that at least part of the void created by removal of at least part of the core may be partially filled with a polymer material.
 8. The orthopedic device of claim 2, wherein the articular layer is a polymeric material.
 9. The orthopedic device of claim 1, further comprising a coating of antifriction high wear material on a surface of said device.
 10. The orthopedic device of claim 1, further comprising at least a second core.
 11. An orthopedic device suitable for minimally invasive deployment using a tubular delivery apparatus, the orthopedic device comprising an elongate core having a proximal end and a distal end, the elongate core comprising a generally rectilinear configuration at substantially body temperatures to enhance self-centering positioning of the orthopedic device when deployed, said elongate core being manipulatable into a substantially straight configuration to permit delivery.
 12. The orthopedic device of claim 11, further comprising an articular layer surrounding at least a portion of the core.
 13. The orthopedic device of claim 11, wherein the core comprises shape memory material.
 14. The orthopedic device of claim 11, wherein the core, when in a generally rectilinear configuration, is substantially non-planar.
 15. The orthopedic device of claim 12, wherein the device is further configured to permit at least partial removal of at least part of the core from the articular layer resulting in a void within the articular layer.
 16. The orthopedic device of claim 15, wherein the device is further configured so that at least part of the void created by removal of at least part of the core may be partially filled with a polymer material.
 17. The orthopedic device of claim 12, wherein the articular layer is a polymeric material.
 18. The orthopedic device of claim 11, further comprising a coating of antifriction high wear material on a surface of said device.
 19. The orthopedic device of claim 11, further comprising at least a second core.
 20. A method of treating an orthopedic joint comprising using a tubular delivery apparatus to minimally-invasively deploy an orthopedic device suitable so that the device forms a substantially non-linear pre-formed configuration in situ at substantially body temperatures to enhance self-centering positioning of the orthopedic device when deployed.
 21. The method of treating an orthopedic joint of claim 20, further comprising inserting an apparatus at or proximal the situs of deployment to remove at least a portion of the device.
 22. The method of treating an orthopedic joint of claim 20, further comprising creating a gap in the orthopedic joint.
 23. The method of treating an orthopedic joint of claim 20, wherein the tubular delivery apparatus comprises a curved channel.
 24. The method of treating an orthopedic joint of claim 20, further comprising inserting an apparatus at or proximal the situs of deployment to remove at least a portion of the core.
 25. The method of treating an orthopedic joint of claim 20, wherein the substantially non-linear pre-formed configuration is rectilinear. 